Energy Systems, Structures and Processes Essential Standard: Analyze patterns of global climate change over time Learning Objective: Differentiate between weather and climate
Global Climate Focus Question How are weather and climate different? Vocabulary Primary Secondary weather carbon dioxide climate ozone
Is there a difference?
Climate Vs. Weather Climate Long-term weather patterns of an area Weather Current state of the troposphere Short term variations
Climatology The study of Earth s climate and the factors that affect past, present, and future climatic changes
Normals Standard values for a location Average values over a long period of time
Elements of weather and climate 1. Properties that are measured regularly 2. Most important elements a. Temperature b. Humidity c. Cloudiness d. Precipitation e. Air pressure f. Wind speed and direction
Earth s Tilt at Seasonal Change Less direct sun light causes lower temperatures More direct sun light causes warmer temperatures
Seasonal Changes
Natural Impacts on Climate Focus Question: How can you explain the impact of natural climate controls on climate?
Climate Factors That Affect Climate I. Atmospheric Circulation Global winds are another factor that influences climate because they distribute heat and moisture around Earth.
Factors That Affect Climate II. Vegetation Vegetation can affect both temperature and the precipitation patterns in an area. Areas with large amounts of vegetation absorb more sunlight. These areas have low albedo. More sunlight causes an increase of transpiration. More oxygen and water vapor are emitted. Plants also release particles (pollen) that act as condensation nuclei that form clouds.
III. Topography Coastal Regions, areas near water, are warmer in the winter and cooler in the summer Mountains play an important role in the amount of precipitation that falls over an area.
IV. Water Bodies Large bodies of water such as lakes and oceans have an important effect on the temperature of an area because temperature of the water body influences the temperature or the air above it.
V. Latitude As latitude increases, The intensity of solar energy decreases. Tropics Most solar radiation, generally warm Between Tropics of Capricorn and Cancer The Sun s rays are most intense
Climate Regions Temperate Between 23.5 and 66.5 Latitude North and South of the equator Mild temperatures Polar 66.5 latitude North and South to the Poles Cold Temperatures
VI. Elevation Elevation or height above sea level, is another factor that affects climate. The higher the elevation the colder the climate The elevation of an area determines the amount of precipitation that falls
Climate Global Winds and Pressure Cells
World Climates Focus Question How is the Köeppen climate classification used to describe the world s five major climate groups? What should I learn? What is the Köppen climate classification system? What are humid tropical climates? Contrast the different types of humid mid-latitude climates. What are the characteristics of dry climates? What are the characteristics of polar climates? How do highland climates compare with nearby lowlands?
World Climates The Köppen climate classification system uses mean monthly and annual values of temperature and precipitation to classify climates.
Koeppen Classification System Classified based on temperature and amount of precipitation Tropical Dry Mild Continental Polar
World Climates Humid tropical climates are without winters. Every month in such a climate has a mean temperature above 18 o C. The amount of precipitation can exceed 200 cm per year. There are 2 types of humid tropical climates: Wet Tropical climates and tropical wet and dry climates.
I. Wet Tropical Wet tropical climates have high temperatures and much annual precipitation. An example is a rainforest Sun s intensity consistently high Located on either side of the equator Humid unstable air
World Climates II. Tropical Wet and Dry Tropical wet and dry climates are climates that transition between the wet tropics and the subtropical steppes. Temperature and total precipitation is similar to wet tropical but there are distinct periods of low precipitation.
African Savanna Tropical grasslands with drought resistant trees
World Climates Climates with mild winters have an average temperature in the coldest month that is below 18 o C but above - 3 o C. Climates with severe winters have an average temperature in the coldest month that is below -3 o C.
World Climates Humid Mid-Latitude with Mild Winters A humid subtropical climate is generally located on the eastern side of a continent between 25º to 40º and is characterized by hot, sultry summers and cool winters. The greatest rainfall is in the months of May, June, July and August. A marine west coast climate is found on windward coasts from latitudes 40 o to 65 o and is dominated by maritime air masses. Winters are mild, and summers are cool. This climate is found in a narrow belt in the northern most part of California to southern Alaska.
World Climates Humid Mid-Latitude With Mild Winters A dry-summer subtropical climate is a climate located on the west sides of continents between 30 o and 45 o latitude. It is the only humid climate with a strong winter precipitation maximum. This climate is found only in California.
Humid Mid-Latitude with severe winters There are 2 types of this kind of climate Humid Continental climate and subartic climate Subartic climate is south of the tundra Winters are long and extremely cold An example is Russia
World Climates A dry climate is one in which the yearly precipitation is not as great as the potential loss of water by evaporation. Arid or Desert Great Basin, rain shadow deserts Temperature range 57ºC to 1.7ºC Semi-Arid Steppe Transition zone surrounding desert and separates from humid climates
World Climates Polar climates are those in which the mean temperature of the warmest month is below 10 o C. Nearly always night Extremely cold Very little precipitation Evaporation is very limited Tundra ( treeless region) Ice cap
An Ice Cap Climate Is a Polar Climate
Climate Change
Long-Term Climatic Change Climates change over extremely long periods of time Ice Ages Periods of extensive glacial coverage Most recent ended 10,000 years ago Temperatures dropped 5 C
Long-Term Climate Change Volcanic Eruptions Reduction incoming solar radiation Inject large amounts of dust and sulphur dioxide gas into the stratosphere that scatter incoming solar radiation. Studies indicate a global cooling of 0.3%C lasting 1 to 2 years. Incoming solar radiation reduction can be offset by an increase in diffuse radiation and by the absorption of outgoing terrestrial radiation (the greenhouse effect).
Short-Term Weather Change Caused by regular variations in daylight, temperature, and weather patterns Volcanic eruptions inject dust and gases into the lower atmosphere. Examples: Seasons El Nino (Warm ocean current)